1. Field of the Invention:
The invention generally relates to impact absorption systems and more particularly to an improved vehicular impact absorption system for arresting impacting vehicles at the lowest possible deceleration level, whereby smoother and safer occupant deceleration for an enlarged class of vehicular impact weights is facilitated.
2. Description of the Prior Art:
Cushion-type crash barrier systems have been employed along the nation's highways since the 1960's. Such systems are intended to provide impact protection for obstacles such as roadway gores, tunnel entrances, as well as bridge and freeway abutments.
The systems of the prior art are typified by the devices and systems generally disclosed in the U.S. Pat. Nos:
______________________________________ Hudson 2,088,087 July 27, 1937 Blackman 2,413,210 Dec. 24, 1946 Sipkin 2,562,957 Aug. 7, 1951 Fitch 3,606,258 Sept. 20, 1971 Fitch 3,643,924 Feb. 22, 1972 Boedecker et al. 3,845,936 Nov. 5, 1974 Fitch 3,856,268 Dec. 24, 1974 Welch 3,876,185 April 8, 1975 Fitch 3,880,404 April 29, 1975 Hildreth 3,951,384 April 20, 1976 ______________________________________
Heretofore, the Federal Highway Administration has approved at least five specific crash barrier systems for highway application. Among these systems are the so-called steel drum and High-Dry Cell sandwich systems which dissipate energy, primarily through a sacrificial crushing of the structure thereof. The other approved systems generally fall within a class of crash cushions which dissipate energy largely by momentum transfer.
Also, certain of the systems heretofore suggested include a capability for altering vehicle direction, upon impact, while other systems, such as the steel drum impact absorption system, tend to "capture" a vehicle, and still others, such as the High-Dry Cell clusters, are designed to perform both functions.
As can be appreciated with those familiar with the design of those barriers having a capability for returning a vehicle back into the flow of traffic such do not require a use structure capable of achieving total dissipation of energy. However, these systems present a potentially dangerous problem of how to avoid an initiation of further crashes as the vehicle is redirected.
Among the advantages realized through the use of systems capable of capturing a vehicle, on impact, is that of avoiding further crashes. However, such systems must be capable of providing for smooth deceleration at relative low G-loads. The conventional steel drum impact absorption system, aforementioned, is, in many instances, capable of achieving a desired relatively smooth and generally safe occupant deceleration on impact. However, among the disadvantages encountered when using such systems are high installation costs, utilization of excessive space, and a generally displeasing appearance.
It should therefore be apparent that there currently exists a need for a durable, economic and practical impact absorption system having an energy dissipating capacity such that significant quantities of energy absorption can be realized at relatively low crushing forces and yet posses an appearance capable of generating confidence in its use while avoiding driver distraction.
It is therefore the general purpose of the instant invention to provide an improved, economical and practical vehicular impact absorption system having an improved appearance and a capability of providing for smoother and safer occupant deceleration for a larger class of vehicle impact weight.